Calculate the amount (mass) of acetaldehyde (C₂H₄O, molar mass = 44.0526 g mol^-¹) that causes a bomb calorimeter with a heat capacity of 12.91 kJ °C^-1 to have a temperature increase from 27.8 °C to 41.7 °C. The Δ_rU for the combustion of acetaldehyde is -1166.9 kJ mol^-1.

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The temperature change is 41.7 °C - 27.8 °C = 13.9 °C. The heat absorbed by the calorimeter is q = C * ΔT = 12.91 kJ/°C * 13.9 °C = 179.449 kJ. Using the reaction energy ΔrU = -1166.9 kJ/mol, the moles of acetaldehyde combusted is 179.449 kJ / 1166.9 kJ/mol = 0.1538 mol. The mass is then 0.1538 mol * 44.0526 g/mol = 6.77 g.

Calculate the Amount (Mass) of Acetaldehyde (C2H4O, Molar Mass =

Calculate the Amount (Mass) of Acetaldehyde (C₂H₄O, Molar Mass =